The present invention relates to a condenser used in a refrigeration cycle in a vehicular air conditioner, for example.
In some of the condensers used in the refrigeration cycle, a reservoir tank, i.e. an accumulator, for storing the refrigerant liquefied by cooling is provided for one of the paired header pipes, and is given the function of a liquid tank, as disclosed in JP-A-8-35744 and JP-A-8-110125.
FIG. 11 is an exploded, perspective view showing a major portion of a conventional product that is disclosed in JP-A-8-35744. In the product, a flat portion B1 with a flat surface B2 is formed on a header pipe B that is one of the paired header pipes, and a flat portion C1 with a flat surface C2 is formed also on a reservoir tank C. A through-hole B3 is formed in the flat portion B1 of the header pipe B at a predetermined location. A through-hole C3 having the same configuration as the through-hole B3 of the header pipe B is formed also in the flat portion C1 of the header pipe C at a predetermined location.
In the product, the through-hole B3 of the header pipe B is aligned with the through-hole C3 of the reservoir tank C, and the through-hole B3 of the header pipe B is joined to the through-hole C3 of the reservoir tank C by hard soldering, whereby the through-hole B3 and the through-hole C3 communicate the inside of the header pipe B with the inside of the reservoir tank C, and form a refrigerant passage D through which a refrigerant flows.
In the conventional product shown in FIG. 11, when the refrigerant leaks from a joining portion for forming the refrigerant passage D, the repair of the leakage requires hermetically sealing of the joining portion over its entire circumference by hard soldering, or the like. Since the refrigerant passage D is formed by joining together the flat surface B2 of the header pipe B and the flat surface C2 of the reservoir tank C, an area of the joining portion forming the refrigerant passage D is large, and the outer circumference of the joining portion is long.
Thus, when the refrigerant leaks from the joining portion forming the refrigerant passage D, much work is needed for its repair. In an extreme case, it is unavoidable to discard the condenser per se.
Accordingly, an object of the present invention is to provide a novel arrangement which enables easy work of repairing the refrigerant leakage from the joining portion forming the refrigerant passage when the leakage occurs.
To achieve the above-noted object, the present invention proposes the use of a connection member that is arranged to be attached to the reservoir tank and one of the heater pipes and to communicate the reservoir tank with the one of the header pipes.
A condenser according to the present invention preferably has the following arrangement:
Arrangement (1):
A plurality of heat exchanging tubes through which refrigerant flows are disposed between a pair of first and second header pipes and arranged in multiple stages to form a core section for cooling refrigerant through the heat exchanging tubes, a reservoir tank is joined to the first header pipe, and the first header pipe is communicated with the reservoir tank by a refrigerant passage. Further, the first header pipe is communicated with the reservoir tank by a connection member having the refrigerant passage, the connection member connects a portion of the first header pipe which is out of a joining portion of the header pipe where the header pipe is joined to the reservoir tank to a portion of the reservoir tank which is out of a joining portion of the reservoir tank where the reservoir tank is joined to the header pipe.
Arrangement (2):
In the arrangement (1), a separator for parting the core section into a condensing portion for condensing and liquefying a gaseous refrigerant and an overcooling portion for overcooling the liquid refrigerant thus formed by the condensing portion is provided within each of the header pipes, each the header pipe is parted, by the separator, into a first chamber communicating with the heat exchanging tubes of the condensing portion and a second chamber communicating with the heat exchanging tubes of the overcooling portion, and the connection member includes, as the refrigerant passage, a first refrigerant passage for communicatively connecting the first chamber in the first header pipe to the reservoir tank, and a second refrigerant passage for communicatively connecting the second chamber in the first header pipe to the reservoir tank.
Arrangement (3):
In the arrangement (2), the connection member includes a first connection member having the first refrigerant passage and a second connection member that has the second refrigerant passage and that is separated from the first connection member.
Arrangement (4):
In any one of the arrangements (1) to (3), an accessory connection port communicated with the refrigerant passage is provided on the connection member so that an accessory part can be attached to the accessory connection port.
Arrangement (5):
In the arrangement (4), a filter for filtering out dust contained in the refrigerant is inserted into and disposed in the refrigerant passage through the accessory connection port, and the accessory part serving also as a sealing plug of the accessory connection port is attached to the accessory connection port.
In the arrangement (1), the first header pipe is communicatively connected to the reservoir tank by a connection member provided with a refrigerant passage, the connection member connects a portion of the first header pipe which is out of a joining portion of the header pipe where it is joined to the reservoir tank to a portion of the reservoir tank which is out of a joining portion of the reservoir tank where it is joined to the header pipe. Accordingly, the joining portions for forming the refrigerant passage are a joining portion between the fist header pipe and the connection member and a joining portion between the reservoir tank and the connection member. Accordingly, the joining areas of the joining portions forming the refrigerant passages are smaller than that in the conventional product shown in FIG. 11 in which the refrigerant passage is formed by joining the first header pipe and the reservoir tank. Further, the length of the outer circumference of the joining portions forming the refrigerant passage is reduced.
When the leakage of the refrigerant from the joining portions forming the refrigerant passage occurs, the location of the leakage can be confined to either one of the joining portion between the first header pipe and the connection member and the joining portion between the reservoir tank and the connection member.
Accordingly, when the refrigerant leaks from the joining portions for forming the refrigerant passage, the circumferential length of the joining portion requiring its repair can be further shortened in comparison to that required in the conventional product shown in FIG. 11. Therefore, the repairing work to hermetically seal the joining portion over its entire circumference by hard soldering or the like is easy.
In the arrangement (2), the refrigerant liquefied by the condensing portion of the core section flows from the first chamber of the first header pipe into the reservoir tank, through the first refrigerant passage of the connection member. The liquid refrigerant in the reservoir tank flows from the tank through the second refrigerant passage of the connection member to the second chamber of the first header pipe, and flows into the overcooling portion where the refrigerant is overcooled. Therefore, even if the core section is parted into the condensing portion and the overcooling portion, the joining portions for forming the refrigerant passages are the joining portion between the first header pipe and the connection member and the joining portion between the reservoir tank and the connection member.
The areas of the joining portion for forming the refrigerant passages can be reduced when comparing with the conventional product shown in FIG. 11, and the circumference length of the joining portion can be reduced. When the refrigerant leaks from the joining portion for the refrigerant passage, the leaking location can be confined to the joining portion between the first header pipe and the connection member or the joining portion of the reservoir tank and the connection member.
Accordingly, even if the core section is parted into the condensing portion and the overcooling portion, when the refrigerant leaks from the joining portion for the refrigerant passage, the circumferential length of the joining portion requiring its repair is shorter than that in the conventional product shown in FIG. 11. As a result, the repairing work to hermetically seal the joining portion over its entire circumference by hard soldering or the like is easy.
In the arrangement (3), in the connection member, a first connection member with a first refrigerant passage is separate from a second connection member with a second refrigerant passage. A broad choice is secured in designing the layout of the first and second refrigerant passages, thereby increasing design freedom.
When the refrigerant leaks from the joining portions for forming both the refrigerant passages, the leaking location can be confined to the joining portion of one of the first connection member and the second connection member. Accordingly, the circumferential length of the joining portion requiring its repair is shorter than that in the arrangement (2). As a result, the repairing work to hermetically seal the joining portion over its entire circumference by hard soldering or the like is easy.
In the arrangement (4), an accessory connection port which communicates with the refrigerant passage and allows an accessory part to be attached thereto is provided on the connection member. Accordingly, accessory part such as a pressure switch, a pressure sensor, or a melting plug can be attached to the accessory connection port. Therefore, there is eliminated the work to set a mounting jig for the accessory part, such as a joint, in an intermediate portion of the refrigerant piping in the refrigeration cycle. This leads to reduction of the cost to construct the refrigeration cycle.
In the arrangement (5), a filter for filtering out dust contained in a refrigerant is inserted into and disposed in the refrigerant passage through the accessory connection port, and an accessory part serving also as a sealing plug of the accessory connection port is attached to the accessory connection port. Therefore, the sealing of the filter within the connection member and the attaching of the accessory part to the connection member can concurrently be carried out. The result is to improve the working efficiency in constructing the refrigeration cycle.
The present disclosure relates to the subject matter contained in Japanese patent application No. Hei. 11-88199 (filed on Mar. 30, 1999), and Japanese patent application No. 2000-49983 (filed on Feb. 25, 2000), which are expressly incorporated herein by reference in their entireties.